Old Olds Fan

Very nice work, the engine compartment, whole car real sharp. No, I wouldn't call that plug lean, it shows a color change half way up the ground electrode which suggests it about where it should be. The sooty look suggests a rich mixture and the blisters might indicate some detonation or pre-ignition. "Ideal mixture reading on a spark plug is a orange/tan/caramel color on the insulator and bottom half of the ground tab with a brown/honey to grey look on the threaded base ring."

EightballZ

honestly the engine has only around 80 mls on it...but its running a little hot so i was worried about the mixture. i know rebuild engines may run hotter during break in...

i didnt noticed any detonation. engine is @ 18° initial and all 36° in @ 3.000 RPM with good german 98 ROZ octane fuel. as long as the passenger side header is leaking at the connection to the exhaust its probably to loud to hear any detonation...except the "bang" shes doing while rolling out in the 1st gear after a strong pull due to that leak

MDchanic

Just remember that that 10.25:1 engine was made to run on 100 to 102 RON octane, so you're about 2-4 points low.

- Eric

EightballZ

good point. i forgot how this RON to AON stuff works...google said:

Normal 91 RON = (91RON+82,5MON)/2 =87,75 AON
Super 95 RON = (95RON+85MON)/2= 90 AON
Super Plus 98 RON = (98RON+88MON)/2= 93 AON

last fuel i gave her was 5 gal. of 102 RON (88 MON) = 95 AON

Old Olds Fan

Your correct with the numbers and you've got better gas than we get at our local gas stations, but I still believe your probably running to much total timing. I'm also not surprised that you had starter problems at 18* initial, personally I'd pull some advance out and run a few more miles and check the plugs again. You might run a compression test, 180 psi was usual for your engine, it will tell you, to some degree, what you comp. ratio is currently, maybe when you pull the plugs for the next read.

MDchanic

Where did you get that from in his post?

He's got 93 AKI octane, just like we have here in the US, which may be a bit low for his engine (depending mostly on his cam).

- Eric

cutlassefi

U.S. grade level 93 is fine for any aluminum headed 10.25:1 application. I've even done 10.0:1 on an iron headed 455 with 91.

Kay left you an email.
All the best.

EightballZ

don't have starter issues with 18° initial..its fine after i replaced it with a new one. cranks like hell now.

its got that much initial so i reach 36° total. got to fix the exhaust first to tell if it pings...but after the first rides i did not notice any pings so far.

i got an accel adv. recurve kit. i replaced only the springs first but adv. was always all in below 3.000 RPM. so i changed the weights only and used the old springs, which works for now all 36° in @ 3.000 RPM.

maybe retard 2°? so its 16° initial and 34° total.

MDchanic

Oh, right - it's been a long-running thread. Forgot he'd installed aluminum Edelbrock heads, which reduce octane requirements.

Thanks for reminding me.

- Eric

Old Olds Fan

He's got 93 AKI octane, just like we have here in the US, which may be a bit low for his engine (depending mostly on his cam).

"last fuel i gave her was 5 gal. of 102 RON (88 MON) = 95 AON"

also for Wikipedia:
Aral Ultimate 102 in Germany 102 88"Shell V-Power" in Italy and Germany 100 88so I figure they probably have better gas than we do, I have a real hard time finding anything better than 91 in south Florida, at the main line stations. I buy AP Racing fuel of 96 octane for $8.60 a gallon, at their pumps, but I don't count that.

MDchanic

I took this to mean that the fuel pump he used in Germany was labeled 98 Octane, which would be the rough equivalent of 93 octane in the US:
I may be mistaken. Even when everyone in a discussion is from the same country, we have problems with understanding each other sometimes.
It can easily be worse when we're talking across an ocean.

I'm sorry that 93 octane is hard to find where you are. Everywhere I go up here has 93, so I never really thought about it. The only place in the US that I had heard of that seemed to have no higher octane than 91 up till now was California.

- Eric

cutlassefi

Really? I'm down there all the time and I see 93 at a lot of places. I'll make a note of it next time I'm there.

EightballZ

hey guys....do you think autolite ar3911 is too cold for this application?